Preheat the oven to 400°F. Line a large, rimmed baking sheet with high-heat-resistant parchment paper, or use a 9x13-inch glass baking dish. Wash the carrots, dry them well, and peel them.
If using large carrots, halve them crosswise and then halve their thick part lengthwise. Your goal is to have similarly sized carrot chunks. If using small carrots, you can leave them whole.
In a large bowl or directly in the pan, toss the carrots with olive oil, honey, kosher salt, and black pepper.
Spread the carrots on the prepared pan in a single layer. Roast until they are tender and browned, 10-15 minutes per side. Serve immediately.
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Notes
While you can use bagged baby carrots, their water content is higher, so it's not easy to get them caramelized (though it's not impossible). They'll require more time in the oven despite their small size. It's best to use young, firm, dry carrots. The small, 5-inch ones, usually sold in bunches with their greens still attached, are perfect. But you can also use mature carrots and cut them.
I prefer peeling the carrots because this gives them a better texture when cooked. But you can leave the peel on if you wish.
Add a teaspoon of chili powder and a pinch of cayenne pepper for a sweet-spicy flavor combination.
You can keep the leftovers in a sealed container in the fridge for 3-4 days. Reheat them gently, covered, in the microwave at 50% power, or slice them and add them cold to a salad.